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STI Thread Plug Gages Manufactured to ASME B18.29.1

STI thread plug gages made to ASME B18.29.1 - Helical Coil Screw Thread Inserts--Free Running and Screw Locking (Inch Series), will have a different no go major diameter than STI thread gages made to MIL-T-211309/A-A-59158.

ASME B18.29.1 does not list tables of gage sizes, but instead states to make the gages per the formula in ASME B1.2.

The major diameter of a no go plug is made to the standard formula of “NoGo P.D. + 0.43301270P.

Since the major diameter of a no go plug gage is only a clearance dimension and does not check anything, either gage standard is correct and completely functional.

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